Zinc air cells typically comprise an anode can and a cathode can. The anode can and cathode can each typically have a cup shaped body with integral closed end and opposing open end. After the necessary materials are inserted into the anode and cathode cans, the open end of the anode can is typically inserted into the open end of the cathode can with electrical insulating material therebetween and the cell securely assembled by crimping. The anode can may be filled with a mixture comprising particulate zinc. Typically, the zinc mixture becomes gelled when electrolyte is added to the mixture. The electrolyte is usually an aqueous solution of potassium hydroxide, however, other aqueous alkaline electrolytes can be used.
Zinc air cells have an anode can top that has traditionally been made from a clad tri-metal sheet having two exposed surfaces—copper to the inside and nickel to the outside of the cell—with a core of stainless steel for strength. If the electrolyte creeps past the copper and around to the stainless steel or nickel layer, then internal gassing will result and later leakage may be found on the external surface of the anode can top, grommet, or outer can. This internal gassing may cause component damage that results in poor cell performance.
There is a need, therefore, for an anode can material that would not suffer from the problems of dissimilar metals reacting with the electrolyte and that can also be compatible with the internal chemistry of the zinc anode and alkaline electrolyte of the cell itself.